Why would an ex block you

My ex and I dated for five years. We broke up two months ago. She wanted the breakup, and I didn't tell her, but deep down, I wanted to break up as well. I literally just told her, I'm okay with breaking up, but let's not block each other on anything. She only ended up blocking me on her TikTok. Whatever, I don't care. However, my friend, who still follows her, said she posted a video about how glad she was not to be with some trashy guy, something along those lines. Obviously, I wasn't happy about that because we agreed to end things on good terms. We were on good terms. I wasn't talking crap about her or anything, so I texted her and confronted her. About it not even necessarily being rude to her, but asking her why she is talking crap about me, she ends up finding out I've been with other women since the breakup. She cusses me out and blocks me. Then, just recently, her little sister, which I can't stand, comments on one of my TikTok reposts and says some snarky comment. I block her sister, but even though my ex went a bit crazy, I'm still hurt she blocked me, especially after five years of a relationship. Should I try reaching out to her to ask why, or should I just wait and see if she unblocks me? I have no intention of ever getting back with her, but I don't like the idea of trying to erase. Someone you've been with for 1/5 of your life; any advice?